Monthly Archives: August 2017

The 8th and 9th of August 2017 has produced probably the most miserable weather of this summer.

A rainfall event that began just after 8am on the 9th deposited nearly 36mm of rain in the Wanstead area over 14 hours.

The 09-09 total of 33.7mm made it the fourth greatest daily August rainfall since 1960.

The heaviest rain fell in a fairly narrow band, as shown by the official 24hr totals on ogimet.com. The low pressure system also produced a lot of rain for the east coast in the previous 24hrs with Bridlington recording over 56mm.

The rain brings the summer total to 207.7mm, just 0.6mm short of the amount recorded in 1997. Though it has been wet it is still a long way short of the wettest summer on record: some 391mm were recorded here in 1903.

In terms of temperature it has been a chilly start to August; the mean temp currently stands 1.2C below the whole month average. Considering CET it has been the coldest start to the month for 30 years.

In terms of the rest of the summer a look at the ECMWF control run out to 10 days suggests an unsettled start to August with the jetstream centred right over the top of the UK. Things may improve as the Azores high attempts to exert more influence – so perhaps more in the way of sunshine than of late. In terms of heatwaves it is impossible to tell at this range.

1st: Cloudy but with sunny spells developing, these growing longer in length by evening.
2nd: Sunny with just a few light cumulus.
3rd: Sunny start though with plenty of cloud around, this tending to thicken after lunch with odd spot of rain.
4th: Sunny and very warm early then tended to cloud over before sun returned in the late afternoon and evening. Some very unstable low to mid level cloud.
5th: Sunny with just a few cirro-cumulus. Feeling very warm with cloud bubbling up in the evening, however forecast storms failed to materialise.
6th: Sunny with cirrus and dotted cumulus. This tended to thicken late morning though sun stayed out and became hot and humid.
7th: Sunny with lots of high-level cirrus and cumulus most of the day.
8th: Bright but mostly cloudy start, the cloud tending to vary through the day. Sunny after 4pm. Warm overnight.
9th: Bright but mostly cloudy start, the cloud tending to break and vary through the day.
10th: A mostly sunny morning and lunchtime until 2pm when it clouded over.
11th: Cloudy with some bright breaks at first. Cloud thickening with rain by noon, this falling sporadically before getting going after 5pm and stopping by 3am.
12th: Cloudy, damp and close start.
13th: Sunny with variable cloud until noon when there were just bright spells.
14th: Cloudy but with a few breaks around mid morning. Turning cloudy again before sunny spells in the evening.
15th: Cloudy with some sporadic rain as warm front blew through and close. Very limited brightness.
16th: Cloudy with some bright spells. Feeling warm and humid.
17th:Sunny with just a few cirrus drifting around. Feeling hot, cloud thickened from the west in the late afternoon.
18th: Sunny with variable cirrus and cirro cumulus through the day. Feeling very warm. Storms began building with supercell to west of London and over Chilterns.
19th: Cloudy, dull start and very humid with heavy mist – the cloud tended to lift to give sunny spells in the afternoon.
20th: Drizzle after shower before obs time, then showers through to 1pm.
21st: Cloudy start but with sunny spells developing. Clouded over in evening with intermittent heavy rain at 11pm and through the early hours.
22nd: Cloudy but with sunny intervals developing around noon. Heavy showers developing with thunder at 2.30pm and 3.07pm.
23rd: Bright with variable cloud
24th: Cloudy with light, showery rain from northerly airstream that originated in the Med.
25th: Cloudy with light rain just after obs time.
26th: Cloudy with occasionally rain. Feeling warm and a late clearance. Breezy and chilly overnight.
27th: Cloudy but bright and sunny spells developing. A very heavy shower at 1pm.
28th: Bright start but clouding over.
29th: Sunny start with cloud increasing after noon to leave overcast before patchy rain moved in. This falling more heavily at 5pm before clearing to further showers. More rain overnight before a strong squall arrived at 2.45am and lasted an hour with further bursts of rain through the night – two claps of thunder and lightening during squall.
30th: Sunny with variable cloud through the day. Very warm in the sunshine
31st: Sunny with variable cloud throughout the day.

Sunsets

With the sun lower in the sky at this time of year there’s often a great opportunity for a decent sunset

Typical April days of sunshine and showers were in short supply. There were some stunning sunsets, including this one on the 30th

Sunset on Wanstead Flats

Sunset Southwark Bridge

It was a month with some amazing sunsets. This one, on April 30th, happened just as the sky cleared before dusk

I took this yesterday evening. Windless, still and humid at ground level it was fascinating to look skyward and see the multi-level cloud continue to build into strange shapes, illuminated from below by the setting sun. A wonderful weekend for cloudspotting.

Sunset on 31st looking across Wanstead Flats. July was a classic summer month for weather

sunset overlooking Wanstead Flats 2nd August

A stunning example of sunlight illuminating the underside of cloud at sunset was seen mid-month

Satellite images

Ophelia

Both the 2013 storm, left, and the 1987 storm followed a similar track as shown on these satellite pictures

On 25th a perfect curl could be seen on a depression centred off the west coast of Irleland. The rain associated with this low pressure brought the month’s highest daily rainfall total: 23.4mm (the system bringing 27.5mm) – a thoroughly miserable Bank Holiday Monday where it rained ALL day, from 6am until 9.30pm. It was yet another example of how much even frontal rainfall can vary over a small area.

This satellite picture taken on December 27th, 2014, shows the LP clearing through to leave us in clear, deep cold air